This invention is a novel color identifying device which is provided with an ideal emitter to supply a stable light source. Its emission is very similar to sunlight.
In FIG. 1, the color identifying device includes an emitter 1, an amorphous photosensor 2, an amplifier 3, an analog digital converter (ADC) 4 and a microprocessor 5. The emitter 1 supplies the sun-like light to a testing object 6, and the amorphous photosensor 2 receives the reflected light. The signal generated from the photosensor 2 are amplified and converted by the amplifier 3 and ADC 4, respectively. Finally, the digital signal are calculated to indentify the color of the tested object 6 by the microprocessor 5.
For common sensors, such as heat sensitive resistors, light sensitive resistors, infrared sensors, etc., the survey of physical volume is depended on object or environment. Object tested by amorphous photosensors 2 does not emit light itself and the emitter 1 has to be used for supplying a background light source. This light source must meet very rigorous conditions described as follows.
1. A background light source should not heat that the temperature effect affects the testing result of sensor. Besides, if the light source has the heating phenomenon in evidence, it implies that the light source consumes much energy, having bad influence on a portable device.
2. The light source must be stable and never glitter. If the light source is unstable, light reflected by an object changes so that it is difficult to sample.
3. Light must be very similar to sunlight, because sunlight contains various visible light to reveal the true colors of object. If a light source trends to some visible light (for example, a tungstem bulb trends to yellow light), it is impossible to identify the true colors of object.
However, emitters 1 used nowadays in color identifying devices, such as luminescent lamps and tungsten bulbs, cannot satisfy the three fundamental conditions described above.